The present invention relates to couplers and, in particular, to a coupler for connecting the shaft of an auger (e.g. an ice or earth drilling auger) to a powerhead.
A variety of types of augers, including spiral fluted augers are used in many different applications. Some applications use a horizontally positioned auger to convey materials. Some applications use a vertical auger for boring holes in soil or ice, such as during winter sport fishing.
The latter ice augers are typically sold in standard lengths and are fastened to the power take-off shaft (PTO) of a power head that includes a gasoline engine and reduction gear assembly. The auger typically includes a cylindrical head coupler having a transverse hole that mounts in telescoping relation to the PTO shaft. A threaded bolt is passed through aligned holes in the head coupler and PTO and fastened to secure the auger to the power head. Extensions shafts can be added in a similar fashion upon aligning and fitting threaded or pin fasteners to holes at the auger and any extension(s).
The length of the resulting power head and auger/extension assembly can present an inconvenience when transporting or storing the assembly. It is therefore desirable to break the assembly down for transport or storage, but which is time consuming and difficult under cold weather conditions, such as when ice fishing.
The present coupler was developed to provide a mechanism for readily dismantling an auger and/or extension piece(s) from a power head. The auger, power head and extension pieces can then be easily stored and reassembled when next needed. In one construction, the coupler comprises a threaded collar that is adapted to mount to a PTO shaft. A mating stub shaft of suitable length and captured, knurled hand nut or collar separately mounts to an auger head coupler. The stub shaft indexes in non-rotational engagement with the PTO collar and the captured threaded hand nut draws the auger and power head together.
In another construction, a non-rotationally mounted PTO collar provides several detents that interconnect with resiliently biased projections (e.g. balls) at an auger collar.
Attachment of the auger is effected by releasing tension of the projections (e.g. pulling or rotating the collar to release tension on the balls), slipping the auger collar over the power head collar and engaging the projections with the detents.
In yet other embodiments, the PTO shaft can include a key (e.g. pin or spline key) that mates with a keyway at an auger head coupler. The auger coupler can include means for resiliently biasing the auger coupler or PTO shaft to latch the key in non-rotational engagement with a provided keyway (e.g. slot, groove or channel). The PTO shaft may also include a surface shaped to non-rotationally interlock with a surface of the auger. A resiliently biased latch means maintains the interlocked condition, when attached, and flexes under certain conditions to release the auger.